Water heater



Jan. 4, 1944.

N. WAGNER WATER HEATER Filed NOV. 28, 1941 2 Sheets-Sheet 1 \w QQN WWW Nm i y A Q m l m a W Q11: 1. W A

1944- v A. N WAGNER 2,338,368

WATER HEATER Filed Nov. 28, 1941 2 Sheets-Sheet 2 1N VENT 0R.

I Arrm EY.

Patented Jan. 4, 1944 WATER HEATER Anthony N. Wagner, Chicago, Ill.,assignor to Pullman-Standard Car Manufacturing Company, Chicago, 111., acorporation of Delaware Application November 28, 1941, Serial No.420,789

1 Claim.

The invention relates to a device for heating water utilizing steam asthe heating medium and primarily intended for use in railway cars.

An important object of the invention is the provision of a water heaterfor railway cars which may be used vertically, horizontally, or at anyangle for application to any type of car.

A further object of the invention is to provide a water heater havingthe highest efliciency in the transfer of heat from the heating mediumto the water to be heated.

A still further object of the invention is the provision of a waterheater wherein the heating element is so disposed that the water to beheated completely surrounds such element to prevent the loss of heatfrom the element to surrounding atmosphere and insure full heat transferbetween the heating element and the water.

Another object of the invention is the provision of a water heater oflight weight adapted to be fabricated from light weight materials andintegrated by welding.

The foregoing and other objects are attained by the arrangement morefully hereinafter to be described and illustrated in the accompanyingdrawings, in which Fig. 1 is a diagrammatic illustration of a crosssectional view of a railway car showing the water heater and pipingarrangement of this invention as applied therebeneath in end elevation;

Fig. 2 is a plan View of the water heater and piping arrangement showingthe relation of the various elements including the water supply tank;

Fig. 3 is a longitudinal sectional View through the water heaterillustrating the details of construction thereof and showing therelation of the ports of entry and exit for the heating medium and thosefor the water to be heated; and

Fig. 4 is a cross sectional view through the water heater showing therelation of the finned inner heating element with the outer water cas-The water heater of this invention is so designed that it may beconnected directly to the main steam line of a railway car, whichnormally operates at a pressure of approximately thirtyfive (35) lbs.,as a source of steam for the heating element of the heater, but which isadapted also to function and preferably is connected to a source ofsteam at a pressure less than that of the main train line in order tohave the steam trap for the heater operate at a pressure low enough toreduce the noise of operation thereof. The Water heater may be connectedto operate from the car heating system, which operates at reducedpressure (approximately 20 lbs.) or it may be connected to the trainline through a pressure reducing valve set to provide the de-' siredreduction. It is entirely possible, however, to operate the heaterwithout benefit of either a pressure reducing valve or a steam trap bymerely providing a choked or reduced passage between the main train-lineand the heater and a slow bleeding passage from the heater to atmosphereaffording a constant drain for the disposition of condensation.

In the drawings, i0 represents diagrammatically a railway car having anunderframe ll and including a center sill i2 and having a side frame it.An underneath equipment housing It is disposed beneath the car andsup-ported from the center sill I2, and in which, in actual practice,the invention is adapted to be disposed. A water supply tank i5 islocated under the car in which air pressure is maintained to raise thewater in suflicient volume to the car interior and which is filled withwater by means of lead-in pipes 16 from opposite sides of the car andfilling valves [1, and all of which form no part of the invention hereinspecifically claimed.

Water from the air pressure supply tank is drawn oif by means ofconnection it through a shut-off valve i9 and piping 2G and 2!,including a check valve 22 permitting the water to flow in only onedirection to the water heater 25 through an inlet connection 23 disposedon the under side of the heater and after being heated, flows from theheater through an outlet connection 24 on top of the heater and thencethrough piping 26 to an adjustable mixing valve 21. A drain valve 28 isdisposed between the piping 2t and 2!. From the piping 2c, the coldwater also branches through piping 29, including a one way check valve36, to the mixing valve 21, whereby the hot water entering the mixingvalve may be tempered to the desired degree before flowing therefromthrough outlet 30 into vertical pipe 3| and transverse pipe 32 fordistribution to the Various washstands and fixtures throughout the carinterior by means of pipes 33 disposed within the opposite side walls.Cold water is supplied to the washstands and fixtures by means of pipes35 also disposed within the opposite side Walls.

The water heater 25, as shown, is direct-connected to the main trainline 35 as a source of steam for the heating element thereof, by meansof piping 31, but with a pressure reducing valve 38 interposed betweenthe trainline and the heater in order to bring the pressure down to apoint where the steam trap 39 at the discharge end of the heater willfunction quietly without disturbing occupants of the car. The maintrainline 35 is located outside of the equipment housing l4, while theheater 25 is located therein with piping 31 afiording a connectiontherebetween and piping 40 connects the discharge end of the heater withthe trap 39 which is also located outside of the housing I4. Thus itwill be seen that the extreme heat from the trainline and the moistureof condensation from the steam trap is avoided in the equipment housing,and, further, as more fully hereinafter to be described, the heater 25is so designed and constructed as to reduce the heat loss therefrom tothe interior of the housing.

The details of construction revealing the operation of the water heater25 are best illustrated in Figs. 3 and 4 from which it will be notedthat the heater comprises an outer cylindrical casing 4| having an endclosure member 42 secured at one end oi the casing by welding and havingan outer radially disposed flange 43 secured by welding at the oppositeend of the casing for attachment to a flange plate 3 on header 45 bymeans of bolts 45. The flange plate 44 is secured to the header 45 bywelding, and, when bolted to the casing ll with a gasket ll between theflange 43 and the flange plate, provides a water-tight receptacle forthe water to be heated. The header provides inlet and outlet openingsfor the steam from the heat transfer action with which the waterentering the heater 25 is raised to the desired temperature as the waterand the steam circulate through the heater in heat exchange relation.

The heating element, as constructed, forms a part of the header l and isadapted to be mounted in the heater casing ll with the header at thetime of assembly. The header is provided with an opening 48 having asleeve #39 secured therein and extending therebeycnd for attachment of afinned tube heating element 5!], the adjacent end of which is disposedabout and secured to the sleeve 49 and which extends axially from theheader 45 within the casing 4| approximately to the end closure plate ofthe heater 25, where it is sealed by an end closure plate 5! weldedtherein so that water entering the heater through connection which isdisposed adjacent one extremity of casing ll, must flow over the fulllength of the finned heating element 55. to reach the outlet connection2t, which is disposed adjacent the opposite end of the casing ll,thereby obtaining the full heat exchange value of the element. The fins52 on the tube 5 .3, as shown are integral. therewith and comprise aseries of integral prongs turned from the body metal of the tube andwhereby the utmost radiation and transfer of heat from the element Ellto the water flowing thereabout is obtained, but any other form ofheating element, either plain or finned, having the necessary radiatingsurface may be utilized if desired.

The header .5 is provided with an opening 53 directly opposite theopening 33 and through which steam is admitted from pipe 3'5, Theopening is threaded to receive a fitting 53 screwed into the opening andinto which the steam pipe 37 is threaded. The fitting 5t has a lead-inpipe 55 extending therefrom into the tube 55 to emit the steam enteringfrom pipe '31 at or near the far end of the finned tube 58 so that thesteam has to travel the full length of the heating chamber and therebyinsure the utmost efficiency in the heat exchange action with the waterin casing 4|. The free end of pipe 55 is braced in the tube 50 by meansof a Z-shaped supporting clip 56 extending between the walls of tube 50through the slotted end of the pipe 55. After passing the full length ofthe heating element, the steam from pipe 55 is exhausted through a thirdopening 51 disposed at the side of header and into which pipe 40 isthreaded and. leads to the trap 39 Where accumulated condensate isdrained.

By the disposition of the heating element at the center of the casing 4|and completely surrounded by the water circulating through the heater,it will readily be seen that the greatest efiiciency in the heatexchange action between the steam in the finned tube 50 and the waterthereabout in casing 4| will be obtained with the smallest possible lossto the surrounding atmosphere, since the steam heating element is notexposed to the atmosphere at any point but gives up its heat directly tothe water to be heated, which insulates the heating element from theatmosphere. By reason of the fact that the surface temperature of theheater 25 is so much lower than a heater where the source of heat mightbe disposed at the perimeter and gives oil so little heat to theatmosphere, this heater may be disposed in the relatively confined spaceof the equipment housing |4 without unduly raising the temperature ofthat space.

From an inspection of Figs. 2, 3, and 4, it will be seen that inoperation, high pressure steam from the trainline 35 passes through thepressure reducing valve 38 to be reduced to a pressure corresponding tothat at which it is desired for the system tooperate and such as tocause the trap 33 to function with the least amount of noise. From thevalve 38, the steam passes through pipe 3! to the inlet pipe into thefinned tube 50 at the inner end, thence traveling the full length of theheating element tube to heat the water in casing 4|, passes through theheader 45 into the pipe 40 leading to the steam trap 39 where thecondensate collecting in the system is discharged. While the steampasses through the heating element 50, water flows through the casing 4|to be heated by contact with the heating tube and fins 52. The water isadapted to flow over the full length of the heating element by thedisposition of the inlet and outlet connections 23 and 24 at the extremeopposite ends of the casing 4|, so that the full benefit of the wholelength of the heating element is obtained. Water from the air pressurestorage tank enters the casing 4| through connection 23 from piping 2|]and 2| and flowing therethrough in heat exchange relation with the steamheated element 50 passes through pipe 26 into the mixing valve 21. Themixing valve is thermostatically controlled, and, having both hot andcold water connections, mixes the two streams of water to provide waterat the temperature desired and for which the mixing valve may beadjusted. From the mixing valve, the water is distributed throughout thecar interior by means of piping 3|, 32, and 33.

It is desirable that the cold water entering the casing 4| should alwaysdo so from the bottom of the casing and be emitted from the top, inorder to take advantage of the natural circulation of the water as it isheated and thus increase the efficiency of the water. By the dispositionof the water connections 23 and 24 at 01 posite ends of the heatercasing 4| and the steam inlet and outlet openings 53 and 51 together atone end of the casing, it will be seen that the heater may be disposedin practically any position and have the water piped through the casingin such manner that the cold water enters at the bottom and the hotwater passes out at the top, while he accumulated condensate drainsfreely from the finned tube 50 from any position and so long as theheater is not actually inverted. In the embodiment illustrated, theheater is supported in a horizontal position from the center sill bymeans of brackets 58, which, as shown, comprise an integral part of theend closure plate 42 and the flange plate 44, but may take any formwhich might prove desirable for the particular postion and angularitythe heater is going to assume in any specific installation and may beseparate from the heater or attached as the case may require.

Since the heater is of a built-up nature, it may be fabricated frommaterials of such gauge as to provide light weight in the completedstructure and of any capacity, for the rate at which the heater willraise the temperature of the cold water to that desired will bedetermined by the length of the heating element 50 and easing 4|, andwhich, therefore, may be regulated. at the time of manufacture to meetindividual require ments.

From the foregoing, it will be seen that there has been provided a waterheater of light weight and efiicient design capable of application atany angle and which may be regulated as to size for the desiredcapacity, and in operation is actually insulated by the Water to beheated, and which permits of a simplified piping arrangement.

What is claimed is:

A water heater including a header having inlet and outlet openings, alead-in pipe for the admission of steam removably secured in said inletopening in axial relation thereto and having its emission opening spacedfrom the inlet by the full length of the pipe, a heating elementconcentrically disposed about the lead-in pipe fixedly secured in saidheader and having a closed and ad jacent the emission opening of thelead-in pipe to provide a complete enclosure therefor whereby the steamadmitted travels the full length of the lead-in pipe inwardly from theinlet opening and then full length of the heating element outwardly fromthe steam emission opening in the lead-in pipe to the outlet opening inthe header, said outlet opening being located in the header at one sideof said heating element within the length of the lead-in pipe anddisposed at an angle to said inlet opening, means maintaining saidlead-in pipe and heating element in concentrically spaced relation, aseparate water jacket enclosing said heating element and comprising ashell concentrically disposed about the heating element having one andpermanently closed and a peripheral flange at the opposite end, saidpermanently closed end being located adjacent to but in spaced relationto the closed end of said heating element, means engaging saidperipheral flange for removably securing the Water jacket to saidheader, and inlet and outlet openings in said jacket for circulation ofwater over said heating element, said inlet opening for water beinglocated in the jacket at that end of the heating element adjacent saidsteam emission opening and the water outlet opening being located in thejacket at that end of the heating element adjacent the steam outletopening in the header whereby the water enters the jacket at the hottestpoint of the heating element and traverses the full extent of theheating element in direct heat exchange relation therewith beforereaching the outlet.

ANTHONY N. WAGNER.

